Electric forging machine



Nov. 5, 1940. G. MORA 2,220,535

ELECTRIC FORGING MACHINE Filed Dec. 6, 1939 3 Sheets-Sheet 1 Nov. 5, 1940. MORA ELECTRIC FORGING MACHINE Filed Dec. 6, 1939 3 SheetsSheet 2 NOV. 5, 1.940. a MQRA 2,220,535

ELECTRIC FORGIYG- MACHINE Filed Dec. 6, 19 59 3 Sheets-Sheet 5 Patented Nov. 5, 1940 nuac'raio ronomc MACHINE Grato Mora, London, England, assignor to Omes Limited, London, England, a British company Application December 6, 1939, Serial No. 307,880

I In Great. Britain September 29.19% I 10 Claims. (01. 219-3) This application corresponds to the application of Grato Mora and Omes Limited. Serial No. 28,371/38, which was filed in Great Britain on September 29, 1938.

This invention comprises improvements in or relating to electric forging machines. Electric forging machines are well known in which a workpiece is electrically heated between electrodes and then deformed by mechanical pres sure. For example work can be gripped in avice which constitutes one electrode and pressed against an anvil which constitutes another electrode so that the work becomes heated between the vice and the anvil. Upsetting pressure then; being applied to theend of the work a head formed between the vice and the anvil and if the work is free to slide through the Jaws of the vice the head maybe of great size relatively to the diameter of the workpiece. This process has not, however, hitherto been adapted for economically dealing withsmall workpieces, especially whe these are of cheap material.

According to the present invention in an electric forging machine there are provided in combination two sets of upsetting devices, each upsetting device including means for heating a workpiece electrically and hydraulic pressing means for applying upsetting pressure to the workpiece, and control means interlinking the hydraulic pressing means constructed to 'cause the automatic altemate operation thereof. By this means the operator is enabled to place a workpiece or workpieces in one set of upsetting devices while a workpiece or workpieces is being upset by the other set of devices and the output of the machine is increased. According to one construction according to the invention the cylinders of the hydraulic pressing means of one set are so connected by pressure fluid supply pipes to the cylinders of the other set that when upsetting pressure is supplied to said one set withkept out of the way to the side or the rear. as

this facilitates the quick insertion and removal of the parts.

One embodiment of electric forging machine according to the invention will now be described by way of example, reference being had to the accompanying drawings in which:

Figure 1 is a partly diagrammatic front elevation of the forging machine; 8

Figure 2 shows on an enlarged scale a control 5 valve operating mechanism; and

Figure 3 is a detail sectional view on the line H of Figure 2 showing a releasable catch embodied in said valve operating mechanism.

The electric forging machine comprises a base 10 frame I on the front face of which are mounted two sets of upsetting devices carried on heavy steel shelves 2 secured to the base frame I.

Each upsetting device comprises two hydraulic cylinders 3 for operating upsetting rains I which 15 project .downwardly and operate crossheads 5 working on slides 6 arranged between the shelves 2 and carrying stops 1. Below the rams 4 and in line therewith there are arranged the electrodes. The lowest pair of electrodes 8 consists Q0 of two anvil-electrodes which are connected to the terminals of the secondary winding 8 of a stepdown transformer. The secondary winding of the transformer is indicated diagrammatically and the transformer is located within the base I 25 andis of conventional design. The anvil-electrodes are each provided with the usual watercooling arrangements and with an anvil face ll of special hard alloy of good electrical conductivity. The anvil faces ID are at right angles to the axes of the hydraulic cylinders which are above them. Above the anvil-electrodes 8 there are located a pair of vice-electrodes. The viceelectrodes consist of a pair of movable Jaws Ii and i2, one for each anvil-electrode, which are 35 mounted on the base frame I to slide in a horizontal direction parallel to the front face of the frame. The other jaws l8 of the vice-electrode a-re constituted by a single block located between the jaws H and i2 and of such dimensions that 40 when two workpieces H are r pp d between the fixed jaws l3 and the movable Jaws H and II, the workpieces H are held in line with the rams above and the anvils l8 below. The anvil-electrodes 8 are insulated from the frame and from 45 each other and the electrical circuit extends from one anvil-electrode 8 through one workpiece ll, block IS, the other workpiece H to the other anvil-electrode 8, the workpieces thus being in series one.with another and receiving the same 50 heating current. The workpieces are engaged at their rear ends by the rams 4 and are thereby caused to slide through the vice-electrodes and be upset simultaneously when the workpieces have been heated.

we 6 setting devices.

The two vice jaws II are carried by hydraulic each set are connected by pipes l9 and their lower ends by pipes 29. The pipe 89 of each set of upsetting devices is connected'by apipe'2i to the pipe 20 of the other set of upsetting 'devices. Thus when one pair of rams d are making an upsetting stroke the other pair of rams 4- are being moved upwardly to prepare for a further upsetting stroke.

The outer portion-of the left-hand cylinder "5 is connected by a supply pipe 22 to the righthand portionof thecentral cylinder l8 and to the inner portion of the right-hand cylinder 86, while the outer portion of right-hand cylinder I6 is connected by a supply pipe 23 to-the lefthand 'end of the central cylinder l8 and the-inner-end of the left-hand cylinder I8. Thus when the jaws of the left-hand pair of vice-electrodes are closed the jaws of the right hand pair of vice-electrodes are open.

A supply pipe 24 connectsthe to the supply-pipe 2| leading to the upper end of the left-hand pair of ram cylinders 3 and a supply pipe 25 connects thesupply pipe 23 to right hand pair of ram cylinders 3. Thus when the left-hand pair of rams are making an upsetting stroke,. the left-hand pair of vice-electrodes are clamped'on" the workpieces and the other vice-electrodes are open sertion or fresh workpieces.

The supply pipes 24 and 25 areiurther connectedto a hydraulic valve 26 to which supply pipes 21; 28'leading respectively to a-pressure pump 29 and sump '30 are also joined. Thepum'p 29 and sump 3B are accommodated within the I base frame of the machine and are of conventional design; these parts have therefore been indicated diagrammatically. 7 Thus a single hydraulic valve'may be employed for reversing the direction of'motion of the rams in the cylinders 3, "5:18. a

The valve 26 is'operated by a pivoted lever 3i *from the cross-heads-fi, the mechanism for carry- 55 ing'out the reversing operation be'ing'shown in detail in Figures2 and 3.

60 of theeross-heeas f one or other set of upsetting device's. Thus the right-hand lever 48' is connected to a cross-headoi the right-hand set of upsetting devices and the left-hand lever 4| toa cross-head of 'the left-hand set of up- The'inner end of each lever" M isconnected by a spring 42 and an eye bolt 63* which passes through a hole in thelever 3i and carries at its free end adjusting and lock nuts 44.

45b of the bell-crank lever is is connected by supply pipe 22 the pipe-'2! leading to the upper ends of the to permit the in- A pair of bell-crank'levers 45 forming releasa spring 46- to the frame member 40 so as to be urgedtowards the lever 3| and is provided with'an e'ye through which passes a rod 41 carrying a stop 48 at one end and connected to the lever M at the other end.

The operation of theytlve is effected as follows:

Asthe cross-head 5 of a ram descends on its upsetting stroke (with the parts as shown in Figure 2 the left-hand pair of rams would be descending), the rod 52 is drawn downwardly causing a rotation of lever 4|, the placing of" the spring 42 under tension and the raising of rod il. The lever 3! cannot tilt, however, due to the releasable catch 45 being in engagement therewith. -When'theiramreaches the end of its upsetting stroke, the stop 48 presses against the arm 45b and causes the bell-crank, lever 45 to rock thereby to disengage the notched arm 45a fromthe lever 31, whereupon due to the tension in the spring 42 an arm of the lever 31 is raised tooperate the valve 26. Itwillbe appreciated that the spring 42 connected to the other arm of the lever'3iand to the other set of upsetting devices does not oppose operation of the valve since the ramsto which it is connected have been withdrawn to the top of the stroke and the spring 42 is therefore slack. 'It will be seen that the mechanismioroperating thevalve 26 is automatically tripped by thearrival of the cross-heads on'the right-hand side or left-hand side of the machine at a predetermined tripping. position which represents the end 7 of the corresponding upsetting stroke. Therefore, when the rams on the left-hand side of the machine have fully upset'two workpieces the valve 26 will be tripped'so as to release the cor-' 1 responding vises and to commencea withdrawal they have been upset and insertingfresh ones.v

This machine can economicallyeifect upsetting operations in the manufacture of bolts, motor-' carvalves and like parts which need tobe producedquickly and in large numbers.

Conveniently the axis of the upsetting apparatus inclines rearwardly frem the vertical at an "angle of somewhat less than 10, as this helps the workpieces to remain in place'in the machine when inserted by the operator until the" vise Jaws close upon them. v p

Iclaim: 11 In an electric forging machine, the combi nation of two sets of upsetting devices, each up-; i setting device comprisingelectric heating means for heating a;workpiece' and hydraulic pressing means including hydraulic cylinders for applying upsetting pressureto the said workpiece, means to supply pressure fluid to the hydraulic cylinders, pressure fluid supplypipes connectingthe hydraulic cylinders of one set of upsetting devices to the hydraulic cylinders of the' other set so that when upsetting pressure is supplied to the cylinders of said one set withdrawal pressure is supplied to the cylinders of the other set and vice versa control valve means in the said supply pipes, tappet means for each of the hydraulic pressing means which are engaged by said presshydraulic connection of the hydraulic pressing means of the other set from that of the tappet so actuated whereby automatic alternate operation of the upsetting devices is secured.

. In. an electric forging machine, the combination of two sets of upsetting devices, each upsetting device comprising electrical heating means for heating a work-piece and hydraulic rams for applying upsetting pressure to the workpieces, means to supply pressure fluid to the hydraulic rams and control means interlinking the hydraulic rams constructed to cause the automatic alternate operation of the upsetting devices, control means including valve means controlling the supply of pressure fluid to the rams and means for actuating the valve means operated. by the sets of upsetting devices alternately at the completion of the upsetting strokes of the rams so asto initiate the upsetting strokes of the rams of the other set of upsetting devices 3. In an electric forging machine, the combination of two sets of upsetting devices, each upsetting device comprising electrical heating means for heating a workpiece and hydraulic rams for applying upsetting pressure to the workpieces, means to supply pressure fluid to the hydraulic rams, pressure fluid supply pipes connecting the rams of one set of upsetting devices to the rams of the other set of upsetting devices so that when upsetting pressure is supplied to the rams of one set withdrawal pressure is supplied to the rams of said other set and vice versa, and control means interlinking the hydraulic rams constructed to cause the automatic alternate operation thereof, said control means including valve means controlling the supply of pressure fluid to the rams, and means for actuating the valve means operated by the sets of upsetting devices at the completion of the upsetting strokes of the rams so as to initiate the upsetting strokes of the rams of the other set of upsetting rams.

4. In an electric forging machine, the combination of two sets of upsetting devices, each upsetting device comprising hydraulic pressing mcans for applying upsetting pressure to a workpiece and electrical heating means for heating the workpiece including hydraulically-operated vice-electrodes for gripping the workpiece during the upsetting stroke. means including fluidpressure supply-pipes to supply pressure fluid to the hydraulic pressing means and to the hydraulically-operated vice-electrodes, control valve means in the said supply pipes, tappet means for each of the hydraulic pressing means which are engaged by said pressing means at the termination of its working stroke, each of said tappet means being operatively connected to said valve means to change the hydraulic connection of the hydraulic pressing means and of the vice electrode of the other set of upsetting devices from that of the tappet so actuated as to cause the alternate automatic operation of the hydraulic pressing means and to cause the correspending vice-electrodes to apply gripping force to the workpiece when the hydraulic pressing means apply upsetting pressure and release said force when the upsetting pressure is released.

5. In an electric forging machine, the combination of two sets of upsetting devices, each up setting device comprising hydraulic pressing means for applying upsetting pressure to a workpiece and electrical heating means for heating the workpiece including hydraulically-operated vice-electrodes for gripping the workpiece durating the valve, resilient ing the upsetting strokes, means including fluidpressure supply-pipes to supply pressure fluid to the hydarulic pressing means and to the hydraulically-operated vice-electrodes, said pressure fluid supply pipes connecting the cylinders of the hydraulic pressing means and the hydraulically-operated vice-electrodes of one set to the hydraulic pressing means and hydraulically-operated vice-electrodes of the other set so that when upsetting pressure and gripping pressure is supplied to one set withdrawal and releasing pressure is'supplied to the other set and vice versa, control valve means in the said supply pipes, tappet means for each of the hydraulic pressing means which are engaged by said pressing means at the termination of its working stroke, each of said tappet means being operatively connected to said valve means to open the hydraulic connection of the hydraulic pressing means of the other set from that of the tappet so actuated whereby automatic alternate operation of the upsetting devices is secured.

6. In an electric forging machine, the combination of two sets of upsetting devices, each upsetting device comprising electrical heating means for heating a workpiece and hydraulic pressing means for applying upsetting pressure to the said workpiece, means to supply pressure fluid to the hydraulic pressing means and control means interlinking the hydraulic pressing means of the pair of upsetting devices and constructed to cause automatic alternate operation of the upsetting devices, said control means including a reversing valve adapted alternately to connect the sets of upsetting devices to the pressure! fluid supply, a pivoted lever for operating the valve, resilient connections joining said pivoted lever to the hydraulic pressing means in such a manner that the resilient connections are brought under stress during the upsetting stroke of the upsetting devices to which they are joined, releasable catches adapted to prevent the operation of the valve by the lever under the action of the stressed resilient connections and means connecting the releasable catches to the hydraulic pressing means to release said c'atches at the end of their upsetting strokes thereby to permit operation of the valve.

7. In an electric forging machine, the combination of two sets of upsetting devices, each upsetting device comprising electric heating means for heating a workpiece and hydraulic pressing means including cylinders for applying upsetting pressure to the said workpiece, means to supply pressure fluid to the hydraulic pressing means, pressure fluid supply pipes connecting the cylinders of one set of upsetting devices to the cylinders of the other set so that when upsetting pressure is supplied to said one set withdrawal pressure is supplied to the other set and vice versa, and control means interlinking the hydraulic pressing means of the sets of upsetting devices and constructed to cause automatic alternate operation of the upsetting devices, said control means including a reversing valve adapted alternately to connect the upsetting devices to the pressure fluid supply, a pivoted lever for operconnections joining said pivoted lever to the hydraulic pressing means in such a manner that the resilient connections are brought under stress during the upsetting stroke of the upsetting devices to which they are joined, releasable catches adapted to prevent the operation of the valve by the lever under the action of the stressed resilient connections and means connecting the releasable catches to the hydraulic pressing means to release said catches at the end of their upsetting strokes thereby to permit operation of the valve.

8. In an electric forging machine, the combination of two sets of upsetting devices, each upsetting device comprising hydraulic pressing means for applying upsetting pressure to a workpiece and electrical heating means for heating the workpiece including hydraulically-operated vice-electrodes for gripping the workpiece during the upsetting strokes, means to supply pressure fluid to the hydraulic pressing means and to the hydrarflically-operated vice-electrodes, and control means interlinking the hydraulic pressing means and the vice-electrodes of the sets of upsetting devices, said control means being constructed to cause the alternate automatic operation of the upsetting devices and to cause the vice-electrodes to apply gripping force to the workpiece when the corresponding hydraulic pressing means apply upsetting pressure to said workpiece and to release said gripping force when the upsetting pressure is released and said control means including a reversing valve adapted alternately to connect the hydraulic pressing means and the vice-electrodes of the sets of upsetting devices to the pressure fluid supply, a pivoted lever for operating the valve, resilient connections joining said pivoted lever to the hydraulic pressing means in such a manner that the resilient connections are brought under stress during the upsetting strokes of said hydraulic pressing means, releasable catches adapted to prevent the operation of the valve by the lever under the action of the stressed resilient connections and means connecting the releasable catches to the hydraulic pressing means to release said catches at the end of their upsetting strokes thereby to permit operation of the valve.

9. In an electric forging machine, the combination of two sets of upsetting devices, each upsetting device comprising a plurality of anvil electrodes, hydraulically-operated vice-electrodes for gripping workpieces arranged above each of said anvil-electrodes, said anvil-electrodes and said vice-electrodes being arranged so that work pieces disposed therebetween are electrically in series, means to supply electric current to said electrodes for heating said workpieces and hydraulic rams above said electrodes and in line therewith adapted to apply upsetting pressure to the heated workpieces, the cylinders of the hydraulic rams of each set being connected to the cylinders of the vice-electrodes so that the viceelectrodes grip the workpieces when upsetting pressure is applied thereto and release the workpieces when the upsetting pressure is released, means for supplying pressure fluid to the hydraulic rams and the hydraulically-operated viceelectrodes, supply pipes connecting the cylinders of the hydraulic rams and hydraulically-operated vice-electrodes of one set of upsetting devices to the hydraulic tame and hydraulically-operated vice-electrodes of the other set of upsetting devices so that when upsetting and gripping pressure is supplied to the cylinders of one set, withdrawal and release pressure is supplied to the cylinders of the other set, and control means interlinking the sets of upsetting devices and constructed to cause the alternate automatic operation of the upsetting devices, said control means including valve means controlling the supply of pressure fluid to the rams and vice-electrodes, said valve means being actuated by the sets of upsetting devices alternately at completion of their upsetting strokes so as to initiate the upsetting strokes of the rams of the other set of upsetting devices.

10. In an electric forging machine, the combination of two sets of upsetting devices, each upsetting device comprising a plurality of anvilelectrcdes, hydraulically-operated vice-electrodes for gripping workpieces arranged above each of said anvil-electrodes, said anvil-electrodes and said vice-electrodes being arranged so that workpieces disposed therebetween are electrically in series, means to supply electric current to said electrodes for heating said workpieces and hydraulic rams above said electrodes and in line therewith adapted to apply upsetting pressure to the heated workpieces, the cylinders of hydraulic rams of each set being connected to the cylinders of the vice-electrodes so that the vice-electrodes grip the workpieces when upsetting pressure is applied thereto and release the workpieces when the upsetting pressure is released, means for supplying pressure fluid to the hydraulic rams and the hydraulically-operated vice-electrodes, supply pipes connecting the cylinders of the hydraulic rams and hydraulically-operated vice-electrodes of one set of upsetting devices to the hydraulic rams and hydraulically-operated vice-electrodes of the other set of upsetting devices so that when upsetting and gripping pressure is supplied to the cylinders of one set, withdrawal and release pressure is supplied to the cylinders of the other set, and control means interlinking the sets of upsetting devices and constructed to cause the alternate automatic operation of the upsetting devices, said control means comprising a reversing valve adapted alternately to connect the upsetting devices to the pressure fluid supply, a pivoted lever for operating the valve, resilient connections joining said pivoted lever to the hydraulic rams in such a manner that the resilient connections are brought under stress during the upsetting stroke of the upsetting devices to which they are joined, releasable catches adapted to prevent the operation of the valve by the lever under the action of the stressed resilient connections and means connecting the releasable catches to the hydraulic rams to release said catches at the end of their upsetting strokes thereby to permit operation of the valve.

GRATO MORA. 

